Harry receives a parchment, it is from Hagrid asking him, Ron and Hermione to come to Aragog's burial, he can't face it alone. Neither of the three really want to go. Harry suddenly thinks he might be able to get Slughorn's memory using the Felix Felicis potion.

At the end of the lesson, Slughorn is gone before Harry can ask about the memory.

In the evening Harry takes some Felix Felicis and leaves with his Invisibility Cloak. Following his gut feelings he goes out to Hagrid's. As if illuminating his path a few steps at the time Harry follows his instinct. Through the Entrance Hall he goes outside and finds Slughorn in conversation with Professor Sprout. When Sprout is gone, Harry takes of his cloak. Harry tells Slughorn about Hagrid and Aragog, Slughorn wants to see the Acromantula, mentioning that their venom is very valuable, and he will also join them after getting some bottles of drinks from his office. Harry goes to Hagrid, who doesn't mind Ron and Hermione couldn't come and touched by Slughorn's reaction.

When Slughorn arrives they go to the dead spider. Harry hears some tinkle of bottles as Slughorn exam ins the head, and the glint of a bottle disappearing beneath his cloak as he steps back from the body. Next they burry Aragog and Slughorn gives a small farewell speech.

Back in Hagrids cabin they drink to Aragog. Slughorn is very interested in things like some Unicorn hair in his cabin. Harry does not actually drink and uses a voiceless Refilling Charm to keep the bottles full. Slughorn and Hagrid get more drunk. They sing a song about a dying wizard called Odo. Hagrid finally falls asleep

Harry brings up the subject of Voldemort killing his father and mother. Slughorn, who liked Harry's mother, finally gives in and gives Harry the memory.